Preparation of activated carbon microspheres from phenolic resin with metal compounds by sub- and supercritical water activation

Activated carbon spheres with well-developed mesopores and high mechanical strength were prepared from phenolic resin with a metal catalyst using sub- and supercritical water (SCW) as an activating agent. A rare earth metal chloride (cerous chloride) was used as catalyst. The effects of different activation methods on the porosity and adsorption characteristics of carbon spheres were investigated. All samples were characterized by nitrogen adsorption at 77 K. Results showed that the catalyst could promote the development of pores in SCW. The cerium compound facilitated the development of mesopores with preponderant pore sizes at 4 nm and 7 nm. The catalyst affected the porosity of the porous carbon the most, whereas the effect of the activation methods was secondary. The activation pressure had the least effect.